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978 lines
24 KiB
978 lines
24 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* vhost transport for vsock |
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* |
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* Copyright (C) 2013-2015 Red Hat, Inc. |
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* Author: Asias He <[email protected]> |
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* Stefan Hajnoczi <[email protected]> |
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*/ |
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#include <linux/miscdevice.h> |
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#include <linux/atomic.h> |
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#include <linux/module.h> |
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#include <linux/mutex.h> |
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#include <linux/vmalloc.h> |
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#include <net/sock.h> |
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#include <linux/virtio_vsock.h> |
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#include <linux/vhost.h> |
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#include <linux/hashtable.h> |
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|
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#include <net/af_vsock.h> |
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#include "vhost.h" |
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|
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#define VHOST_VSOCK_DEFAULT_HOST_CID 2 |
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/* Max number of bytes transferred before requeueing the job. |
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* Using this limit prevents one virtqueue from starving others. */ |
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#define VHOST_VSOCK_WEIGHT 0x80000 |
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/* Max number of packets transferred before requeueing the job. |
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* Using this limit prevents one virtqueue from starving others with |
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* small pkts. |
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*/ |
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#define VHOST_VSOCK_PKT_WEIGHT 256 |
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|
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enum { |
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VHOST_VSOCK_FEATURES = VHOST_FEATURES | |
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(1ULL << VIRTIO_F_ACCESS_PLATFORM) | |
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(1ULL << VIRTIO_VSOCK_F_SEQPACKET) |
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}; |
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|
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enum { |
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VHOST_VSOCK_BACKEND_FEATURES = (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2) |
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}; |
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|
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/* Used to track all the vhost_vsock instances on the system. */ |
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static DEFINE_MUTEX(vhost_vsock_mutex); |
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static DEFINE_READ_MOSTLY_HASHTABLE(vhost_vsock_hash, 8); |
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|
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struct vhost_vsock { |
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struct vhost_dev dev; |
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struct vhost_virtqueue vqs[2]; |
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|
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/* Link to global vhost_vsock_hash, writes use vhost_vsock_mutex */ |
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struct hlist_node hash; |
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struct vhost_work send_pkt_work; |
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spinlock_t send_pkt_list_lock; |
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struct list_head send_pkt_list; /* host->guest pending packets */ |
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|
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atomic_t queued_replies; |
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u32 guest_cid; |
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bool seqpacket_allow; |
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}; |
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|
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static u32 vhost_transport_get_local_cid(void) |
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{ |
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return VHOST_VSOCK_DEFAULT_HOST_CID; |
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} |
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|
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/* Callers that dereference the return value must hold vhost_vsock_mutex or the |
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* RCU read lock. |
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*/ |
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static struct vhost_vsock *vhost_vsock_get(u32 guest_cid) |
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{ |
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struct vhost_vsock *vsock; |
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|
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hash_for_each_possible_rcu(vhost_vsock_hash, vsock, hash, guest_cid) { |
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u32 other_cid = vsock->guest_cid; |
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|
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/* Skip instances that have no CID yet */ |
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if (other_cid == 0) |
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continue; |
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|
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if (other_cid == guest_cid) |
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return vsock; |
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} |
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return NULL; |
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} |
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static void |
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vhost_transport_do_send_pkt(struct vhost_vsock *vsock, |
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struct vhost_virtqueue *vq) |
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{ |
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struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX]; |
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int pkts = 0, total_len = 0; |
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bool added = false; |
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bool restart_tx = false; |
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mutex_lock(&vq->mutex); |
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|
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if (!vhost_vq_get_backend(vq)) |
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goto out; |
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if (!vq_meta_prefetch(vq)) |
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goto out; |
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|
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/* Avoid further vmexits, we're already processing the virtqueue */ |
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vhost_disable_notify(&vsock->dev, vq); |
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|
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do { |
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struct virtio_vsock_pkt *pkt; |
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struct iov_iter iov_iter; |
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unsigned out, in; |
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size_t nbytes; |
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size_t iov_len, payload_len; |
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int head; |
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u32 flags_to_restore = 0; |
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spin_lock_bh(&vsock->send_pkt_list_lock); |
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if (list_empty(&vsock->send_pkt_list)) { |
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spin_unlock_bh(&vsock->send_pkt_list_lock); |
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vhost_enable_notify(&vsock->dev, vq); |
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break; |
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} |
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pkt = list_first_entry(&vsock->send_pkt_list, |
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struct virtio_vsock_pkt, list); |
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list_del_init(&pkt->list); |
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spin_unlock_bh(&vsock->send_pkt_list_lock); |
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|
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head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), |
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&out, &in, NULL, NULL); |
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if (head < 0) { |
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spin_lock_bh(&vsock->send_pkt_list_lock); |
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list_add(&pkt->list, &vsock->send_pkt_list); |
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spin_unlock_bh(&vsock->send_pkt_list_lock); |
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break; |
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} |
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if (head == vq->num) { |
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spin_lock_bh(&vsock->send_pkt_list_lock); |
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list_add(&pkt->list, &vsock->send_pkt_list); |
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spin_unlock_bh(&vsock->send_pkt_list_lock); |
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|
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/* We cannot finish yet if more buffers snuck in while |
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* re-enabling notify. |
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*/ |
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if (unlikely(vhost_enable_notify(&vsock->dev, vq))) { |
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vhost_disable_notify(&vsock->dev, vq); |
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continue; |
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} |
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break; |
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} |
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if (out) { |
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virtio_transport_free_pkt(pkt); |
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vq_err(vq, "Expected 0 output buffers, got %u\n", out); |
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break; |
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} |
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iov_len = iov_length(&vq->iov[out], in); |
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if (iov_len < sizeof(pkt->hdr)) { |
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virtio_transport_free_pkt(pkt); |
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vq_err(vq, "Buffer len [%zu] too small\n", iov_len); |
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break; |
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} |
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iov_iter_init(&iov_iter, READ, &vq->iov[out], in, iov_len); |
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payload_len = pkt->len - pkt->off; |
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|
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/* If the packet is greater than the space available in the |
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* buffer, we split it using multiple buffers. |
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*/ |
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if (payload_len > iov_len - sizeof(pkt->hdr)) { |
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payload_len = iov_len - sizeof(pkt->hdr); |
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|
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/* As we are copying pieces of large packet's buffer to |
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* small rx buffers, headers of packets in rx queue are |
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* created dynamically and are initialized with header |
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* of current packet(except length). But in case of |
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* SOCK_SEQPACKET, we also must clear message delimeter |
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* bit (VIRTIO_VSOCK_SEQ_EOM) and MSG_EOR bit |
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* (VIRTIO_VSOCK_SEQ_EOR) if set. Otherwise, |
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* there will be sequence of packets with these |
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* bits set. After initialized header will be copied to |
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* rx buffer, these required bits will be restored. |
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*/ |
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if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SEQ_EOM) { |
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pkt->hdr.flags &= ~cpu_to_le32(VIRTIO_VSOCK_SEQ_EOM); |
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flags_to_restore |= VIRTIO_VSOCK_SEQ_EOM; |
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if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SEQ_EOR) { |
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pkt->hdr.flags &= ~cpu_to_le32(VIRTIO_VSOCK_SEQ_EOR); |
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flags_to_restore |= VIRTIO_VSOCK_SEQ_EOR; |
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} |
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} |
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} |
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/* Set the correct length in the header */ |
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pkt->hdr.len = cpu_to_le32(payload_len); |
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nbytes = copy_to_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter); |
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if (nbytes != sizeof(pkt->hdr)) { |
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virtio_transport_free_pkt(pkt); |
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vq_err(vq, "Faulted on copying pkt hdr\n"); |
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break; |
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} |
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nbytes = copy_to_iter(pkt->buf + pkt->off, payload_len, |
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&iov_iter); |
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if (nbytes != payload_len) { |
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virtio_transport_free_pkt(pkt); |
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vq_err(vq, "Faulted on copying pkt buf\n"); |
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break; |
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} |
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/* Deliver to monitoring devices all packets that we |
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* will transmit. |
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*/ |
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virtio_transport_deliver_tap_pkt(pkt); |
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vhost_add_used(vq, head, sizeof(pkt->hdr) + payload_len); |
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added = true; |
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pkt->off += payload_len; |
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total_len += payload_len; |
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/* If we didn't send all the payload we can requeue the packet |
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* to send it with the next available buffer. |
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*/ |
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if (pkt->off < pkt->len) { |
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pkt->hdr.flags |= cpu_to_le32(flags_to_restore); |
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/* We are queueing the same virtio_vsock_pkt to handle |
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* the remaining bytes, and we want to deliver it |
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* to monitoring devices in the next iteration. |
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*/ |
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pkt->tap_delivered = false; |
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spin_lock_bh(&vsock->send_pkt_list_lock); |
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list_add(&pkt->list, &vsock->send_pkt_list); |
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spin_unlock_bh(&vsock->send_pkt_list_lock); |
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} else { |
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if (pkt->reply) { |
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int val; |
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val = atomic_dec_return(&vsock->queued_replies); |
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/* Do we have resources to resume tx |
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* processing? |
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*/ |
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if (val + 1 == tx_vq->num) |
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restart_tx = true; |
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} |
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virtio_transport_free_pkt(pkt); |
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} |
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} while(likely(!vhost_exceeds_weight(vq, ++pkts, total_len))); |
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if (added) |
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vhost_signal(&vsock->dev, vq); |
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out: |
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mutex_unlock(&vq->mutex); |
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if (restart_tx) |
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vhost_poll_queue(&tx_vq->poll); |
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} |
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static void vhost_transport_send_pkt_work(struct vhost_work *work) |
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{ |
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struct vhost_virtqueue *vq; |
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struct vhost_vsock *vsock; |
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vsock = container_of(work, struct vhost_vsock, send_pkt_work); |
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vq = &vsock->vqs[VSOCK_VQ_RX]; |
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vhost_transport_do_send_pkt(vsock, vq); |
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} |
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static int |
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vhost_transport_send_pkt(struct virtio_vsock_pkt *pkt) |
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{ |
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struct vhost_vsock *vsock; |
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int len = pkt->len; |
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rcu_read_lock(); |
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/* Find the vhost_vsock according to guest context id */ |
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vsock = vhost_vsock_get(le64_to_cpu(pkt->hdr.dst_cid)); |
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if (!vsock) { |
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rcu_read_unlock(); |
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virtio_transport_free_pkt(pkt); |
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return -ENODEV; |
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} |
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if (pkt->reply) |
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atomic_inc(&vsock->queued_replies); |
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spin_lock_bh(&vsock->send_pkt_list_lock); |
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list_add_tail(&pkt->list, &vsock->send_pkt_list); |
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spin_unlock_bh(&vsock->send_pkt_list_lock); |
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vhost_work_queue(&vsock->dev, &vsock->send_pkt_work); |
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rcu_read_unlock(); |
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return len; |
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} |
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static int |
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vhost_transport_cancel_pkt(struct vsock_sock *vsk) |
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{ |
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struct vhost_vsock *vsock; |
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struct virtio_vsock_pkt *pkt, *n; |
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int cnt = 0; |
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int ret = -ENODEV; |
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LIST_HEAD(freeme); |
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rcu_read_lock(); |
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/* Find the vhost_vsock according to guest context id */ |
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vsock = vhost_vsock_get(vsk->remote_addr.svm_cid); |
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if (!vsock) |
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goto out; |
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spin_lock_bh(&vsock->send_pkt_list_lock); |
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list_for_each_entry_safe(pkt, n, &vsock->send_pkt_list, list) { |
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if (pkt->vsk != vsk) |
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continue; |
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list_move(&pkt->list, &freeme); |
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} |
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spin_unlock_bh(&vsock->send_pkt_list_lock); |
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list_for_each_entry_safe(pkt, n, &freeme, list) { |
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if (pkt->reply) |
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cnt++; |
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list_del(&pkt->list); |
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virtio_transport_free_pkt(pkt); |
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} |
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if (cnt) { |
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struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX]; |
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int new_cnt; |
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new_cnt = atomic_sub_return(cnt, &vsock->queued_replies); |
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if (new_cnt + cnt >= tx_vq->num && new_cnt < tx_vq->num) |
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vhost_poll_queue(&tx_vq->poll); |
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} |
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ret = 0; |
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out: |
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rcu_read_unlock(); |
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return ret; |
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} |
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static struct virtio_vsock_pkt * |
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vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq, |
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unsigned int out, unsigned int in) |
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{ |
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struct virtio_vsock_pkt *pkt; |
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struct iov_iter iov_iter; |
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size_t nbytes; |
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size_t len; |
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if (in != 0) { |
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vq_err(vq, "Expected 0 input buffers, got %u\n", in); |
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return NULL; |
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} |
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pkt = kzalloc(sizeof(*pkt), GFP_KERNEL); |
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if (!pkt) |
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return NULL; |
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len = iov_length(vq->iov, out); |
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iov_iter_init(&iov_iter, WRITE, vq->iov, out, len); |
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nbytes = copy_from_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter); |
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if (nbytes != sizeof(pkt->hdr)) { |
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vq_err(vq, "Expected %zu bytes for pkt->hdr, got %zu bytes\n", |
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sizeof(pkt->hdr), nbytes); |
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kfree(pkt); |
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return NULL; |
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} |
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pkt->len = le32_to_cpu(pkt->hdr.len); |
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/* No payload */ |
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if (!pkt->len) |
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return pkt; |
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/* The pkt is too big */ |
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if (pkt->len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) { |
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kfree(pkt); |
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return NULL; |
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} |
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pkt->buf = kmalloc(pkt->len, GFP_KERNEL); |
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if (!pkt->buf) { |
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kfree(pkt); |
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return NULL; |
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} |
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pkt->buf_len = pkt->len; |
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nbytes = copy_from_iter(pkt->buf, pkt->len, &iov_iter); |
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if (nbytes != pkt->len) { |
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vq_err(vq, "Expected %u byte payload, got %zu bytes\n", |
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pkt->len, nbytes); |
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virtio_transport_free_pkt(pkt); |
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return NULL; |
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} |
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return pkt; |
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} |
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/* Is there space left for replies to rx packets? */ |
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static bool vhost_vsock_more_replies(struct vhost_vsock *vsock) |
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{ |
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struct vhost_virtqueue *vq = &vsock->vqs[VSOCK_VQ_TX]; |
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int val; |
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smp_rmb(); /* paired with atomic_inc() and atomic_dec_return() */ |
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val = atomic_read(&vsock->queued_replies); |
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return val < vq->num; |
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} |
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static bool vhost_transport_seqpacket_allow(u32 remote_cid); |
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static struct virtio_transport vhost_transport = { |
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.transport = { |
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.module = THIS_MODULE, |
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|
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.get_local_cid = vhost_transport_get_local_cid, |
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|
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.init = virtio_transport_do_socket_init, |
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.destruct = virtio_transport_destruct, |
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.release = virtio_transport_release, |
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.connect = virtio_transport_connect, |
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.shutdown = virtio_transport_shutdown, |
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.cancel_pkt = vhost_transport_cancel_pkt, |
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|
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.dgram_enqueue = virtio_transport_dgram_enqueue, |
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.dgram_dequeue = virtio_transport_dgram_dequeue, |
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.dgram_bind = virtio_transport_dgram_bind, |
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.dgram_allow = virtio_transport_dgram_allow, |
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|
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.stream_enqueue = virtio_transport_stream_enqueue, |
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.stream_dequeue = virtio_transport_stream_dequeue, |
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.stream_has_data = virtio_transport_stream_has_data, |
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.stream_has_space = virtio_transport_stream_has_space, |
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.stream_rcvhiwat = virtio_transport_stream_rcvhiwat, |
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.stream_is_active = virtio_transport_stream_is_active, |
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.stream_allow = virtio_transport_stream_allow, |
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.seqpacket_dequeue = virtio_transport_seqpacket_dequeue, |
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.seqpacket_enqueue = virtio_transport_seqpacket_enqueue, |
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.seqpacket_allow = vhost_transport_seqpacket_allow, |
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.seqpacket_has_data = virtio_transport_seqpacket_has_data, |
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|
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.notify_poll_in = virtio_transport_notify_poll_in, |
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.notify_poll_out = virtio_transport_notify_poll_out, |
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.notify_recv_init = virtio_transport_notify_recv_init, |
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.notify_recv_pre_block = virtio_transport_notify_recv_pre_block, |
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.notify_recv_pre_dequeue = virtio_transport_notify_recv_pre_dequeue, |
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.notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue, |
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.notify_send_init = virtio_transport_notify_send_init, |
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.notify_send_pre_block = virtio_transport_notify_send_pre_block, |
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.notify_send_pre_enqueue = virtio_transport_notify_send_pre_enqueue, |
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.notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue, |
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.notify_buffer_size = virtio_transport_notify_buffer_size, |
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}, |
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.send_pkt = vhost_transport_send_pkt, |
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}; |
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static bool vhost_transport_seqpacket_allow(u32 remote_cid) |
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{ |
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struct vhost_vsock *vsock; |
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bool seqpacket_allow = false; |
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rcu_read_lock(); |
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vsock = vhost_vsock_get(remote_cid); |
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|
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if (vsock) |
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seqpacket_allow = vsock->seqpacket_allow; |
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rcu_read_unlock(); |
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return seqpacket_allow; |
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} |
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|
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static void vhost_vsock_handle_tx_kick(struct vhost_work *work) |
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{ |
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struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
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poll.work); |
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struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock, |
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dev); |
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struct virtio_vsock_pkt *pkt; |
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int head, pkts = 0, total_len = 0; |
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unsigned int out, in; |
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bool added = false; |
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|
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mutex_lock(&vq->mutex); |
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|
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if (!vhost_vq_get_backend(vq)) |
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goto out; |
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|
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if (!vq_meta_prefetch(vq)) |
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goto out; |
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vhost_disable_notify(&vsock->dev, vq); |
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do { |
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u32 len; |
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|
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if (!vhost_vsock_more_replies(vsock)) { |
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/* Stop tx until the device processes already |
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* pending replies. Leave tx virtqueue |
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* callbacks disabled. |
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*/ |
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goto no_more_replies; |
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} |
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|
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head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), |
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&out, &in, NULL, NULL); |
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if (head < 0) |
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break; |
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|
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if (head == vq->num) { |
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if (unlikely(vhost_enable_notify(&vsock->dev, vq))) { |
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vhost_disable_notify(&vsock->dev, vq); |
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continue; |
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} |
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break; |
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} |
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|
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pkt = vhost_vsock_alloc_pkt(vq, out, in); |
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if (!pkt) { |
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vq_err(vq, "Faulted on pkt\n"); |
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continue; |
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} |
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|
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len = pkt->len; |
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|
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/* Deliver to monitoring devices all received packets */ |
|
virtio_transport_deliver_tap_pkt(pkt); |
|
|
|
/* Only accept correctly addressed packets */ |
|
if (le64_to_cpu(pkt->hdr.src_cid) == vsock->guest_cid && |
|
le64_to_cpu(pkt->hdr.dst_cid) == |
|
vhost_transport_get_local_cid()) |
|
virtio_transport_recv_pkt(&vhost_transport, pkt); |
|
else |
|
virtio_transport_free_pkt(pkt); |
|
|
|
len += sizeof(pkt->hdr); |
|
vhost_add_used(vq, head, len); |
|
total_len += len; |
|
added = true; |
|
} while(likely(!vhost_exceeds_weight(vq, ++pkts, total_len))); |
|
|
|
no_more_replies: |
|
if (added) |
|
vhost_signal(&vsock->dev, vq); |
|
|
|
out: |
|
mutex_unlock(&vq->mutex); |
|
} |
|
|
|
static void vhost_vsock_handle_rx_kick(struct vhost_work *work) |
|
{ |
|
struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, |
|
poll.work); |
|
struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock, |
|
dev); |
|
|
|
vhost_transport_do_send_pkt(vsock, vq); |
|
} |
|
|
|
static int vhost_vsock_start(struct vhost_vsock *vsock) |
|
{ |
|
struct vhost_virtqueue *vq; |
|
size_t i; |
|
int ret; |
|
|
|
mutex_lock(&vsock->dev.mutex); |
|
|
|
ret = vhost_dev_check_owner(&vsock->dev); |
|
if (ret) |
|
goto err; |
|
|
|
for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { |
|
vq = &vsock->vqs[i]; |
|
|
|
mutex_lock(&vq->mutex); |
|
|
|
if (!vhost_vq_access_ok(vq)) { |
|
ret = -EFAULT; |
|
goto err_vq; |
|
} |
|
|
|
if (!vhost_vq_get_backend(vq)) { |
|
vhost_vq_set_backend(vq, vsock); |
|
ret = vhost_vq_init_access(vq); |
|
if (ret) |
|
goto err_vq; |
|
} |
|
|
|
mutex_unlock(&vq->mutex); |
|
} |
|
|
|
/* Some packets may have been queued before the device was started, |
|
* let's kick the send worker to send them. |
|
*/ |
|
vhost_work_queue(&vsock->dev, &vsock->send_pkt_work); |
|
|
|
mutex_unlock(&vsock->dev.mutex); |
|
return 0; |
|
|
|
err_vq: |
|
vhost_vq_set_backend(vq, NULL); |
|
mutex_unlock(&vq->mutex); |
|
|
|
for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { |
|
vq = &vsock->vqs[i]; |
|
|
|
mutex_lock(&vq->mutex); |
|
vhost_vq_set_backend(vq, NULL); |
|
mutex_unlock(&vq->mutex); |
|
} |
|
err: |
|
mutex_unlock(&vsock->dev.mutex); |
|
return ret; |
|
} |
|
|
|
static int vhost_vsock_stop(struct vhost_vsock *vsock) |
|
{ |
|
size_t i; |
|
int ret; |
|
|
|
mutex_lock(&vsock->dev.mutex); |
|
|
|
ret = vhost_dev_check_owner(&vsock->dev); |
|
if (ret) |
|
goto err; |
|
|
|
for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { |
|
struct vhost_virtqueue *vq = &vsock->vqs[i]; |
|
|
|
mutex_lock(&vq->mutex); |
|
vhost_vq_set_backend(vq, NULL); |
|
mutex_unlock(&vq->mutex); |
|
} |
|
|
|
err: |
|
mutex_unlock(&vsock->dev.mutex); |
|
return ret; |
|
} |
|
|
|
static void vhost_vsock_free(struct vhost_vsock *vsock) |
|
{ |
|
kvfree(vsock); |
|
} |
|
|
|
static int vhost_vsock_dev_open(struct inode *inode, struct file *file) |
|
{ |
|
struct vhost_virtqueue **vqs; |
|
struct vhost_vsock *vsock; |
|
int ret; |
|
|
|
/* This struct is large and allocation could fail, fall back to vmalloc |
|
* if there is no other way. |
|
*/ |
|
vsock = kvmalloc(sizeof(*vsock), GFP_KERNEL | __GFP_RETRY_MAYFAIL); |
|
if (!vsock) |
|
return -ENOMEM; |
|
|
|
vqs = kmalloc_array(ARRAY_SIZE(vsock->vqs), sizeof(*vqs), GFP_KERNEL); |
|
if (!vqs) { |
|
ret = -ENOMEM; |
|
goto out; |
|
} |
|
|
|
vsock->guest_cid = 0; /* no CID assigned yet */ |
|
|
|
atomic_set(&vsock->queued_replies, 0); |
|
|
|
vqs[VSOCK_VQ_TX] = &vsock->vqs[VSOCK_VQ_TX]; |
|
vqs[VSOCK_VQ_RX] = &vsock->vqs[VSOCK_VQ_RX]; |
|
vsock->vqs[VSOCK_VQ_TX].handle_kick = vhost_vsock_handle_tx_kick; |
|
vsock->vqs[VSOCK_VQ_RX].handle_kick = vhost_vsock_handle_rx_kick; |
|
|
|
vhost_dev_init(&vsock->dev, vqs, ARRAY_SIZE(vsock->vqs), |
|
UIO_MAXIOV, VHOST_VSOCK_PKT_WEIGHT, |
|
VHOST_VSOCK_WEIGHT, true, NULL); |
|
|
|
file->private_data = vsock; |
|
spin_lock_init(&vsock->send_pkt_list_lock); |
|
INIT_LIST_HEAD(&vsock->send_pkt_list); |
|
vhost_work_init(&vsock->send_pkt_work, vhost_transport_send_pkt_work); |
|
return 0; |
|
|
|
out: |
|
vhost_vsock_free(vsock); |
|
return ret; |
|
} |
|
|
|
static void vhost_vsock_flush(struct vhost_vsock *vsock) |
|
{ |
|
int i; |
|
|
|
for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) |
|
if (vsock->vqs[i].handle_kick) |
|
vhost_poll_flush(&vsock->vqs[i].poll); |
|
vhost_work_dev_flush(&vsock->dev); |
|
} |
|
|
|
static void vhost_vsock_reset_orphans(struct sock *sk) |
|
{ |
|
struct vsock_sock *vsk = vsock_sk(sk); |
|
|
|
/* vmci_transport.c doesn't take sk_lock here either. At least we're |
|
* under vsock_table_lock so the sock cannot disappear while we're |
|
* executing. |
|
*/ |
|
|
|
/* If the peer is still valid, no need to reset connection */ |
|
if (vhost_vsock_get(vsk->remote_addr.svm_cid)) |
|
return; |
|
|
|
/* If the close timeout is pending, let it expire. This avoids races |
|
* with the timeout callback. |
|
*/ |
|
if (vsk->close_work_scheduled) |
|
return; |
|
|
|
sock_set_flag(sk, SOCK_DONE); |
|
vsk->peer_shutdown = SHUTDOWN_MASK; |
|
sk->sk_state = SS_UNCONNECTED; |
|
sk->sk_err = ECONNRESET; |
|
sk_error_report(sk); |
|
} |
|
|
|
static int vhost_vsock_dev_release(struct inode *inode, struct file *file) |
|
{ |
|
struct vhost_vsock *vsock = file->private_data; |
|
|
|
mutex_lock(&vhost_vsock_mutex); |
|
if (vsock->guest_cid) |
|
hash_del_rcu(&vsock->hash); |
|
mutex_unlock(&vhost_vsock_mutex); |
|
|
|
/* Wait for other CPUs to finish using vsock */ |
|
synchronize_rcu(); |
|
|
|
/* Iterating over all connections for all CIDs to find orphans is |
|
* inefficient. Room for improvement here. */ |
|
vsock_for_each_connected_socket(vhost_vsock_reset_orphans); |
|
|
|
vhost_vsock_stop(vsock); |
|
vhost_vsock_flush(vsock); |
|
vhost_dev_stop(&vsock->dev); |
|
|
|
spin_lock_bh(&vsock->send_pkt_list_lock); |
|
while (!list_empty(&vsock->send_pkt_list)) { |
|
struct virtio_vsock_pkt *pkt; |
|
|
|
pkt = list_first_entry(&vsock->send_pkt_list, |
|
struct virtio_vsock_pkt, list); |
|
list_del_init(&pkt->list); |
|
virtio_transport_free_pkt(pkt); |
|
} |
|
spin_unlock_bh(&vsock->send_pkt_list_lock); |
|
|
|
vhost_dev_cleanup(&vsock->dev); |
|
kfree(vsock->dev.vqs); |
|
vhost_vsock_free(vsock); |
|
return 0; |
|
} |
|
|
|
static int vhost_vsock_set_cid(struct vhost_vsock *vsock, u64 guest_cid) |
|
{ |
|
struct vhost_vsock *other; |
|
|
|
/* Refuse reserved CIDs */ |
|
if (guest_cid <= VMADDR_CID_HOST || |
|
guest_cid == U32_MAX) |
|
return -EINVAL; |
|
|
|
/* 64-bit CIDs are not yet supported */ |
|
if (guest_cid > U32_MAX) |
|
return -EINVAL; |
|
|
|
/* Refuse if CID is assigned to the guest->host transport (i.e. nested |
|
* VM), to make the loopback work. |
|
*/ |
|
if (vsock_find_cid(guest_cid)) |
|
return -EADDRINUSE; |
|
|
|
/* Refuse if CID is already in use */ |
|
mutex_lock(&vhost_vsock_mutex); |
|
other = vhost_vsock_get(guest_cid); |
|
if (other && other != vsock) { |
|
mutex_unlock(&vhost_vsock_mutex); |
|
return -EADDRINUSE; |
|
} |
|
|
|
if (vsock->guest_cid) |
|
hash_del_rcu(&vsock->hash); |
|
|
|
vsock->guest_cid = guest_cid; |
|
hash_add_rcu(vhost_vsock_hash, &vsock->hash, vsock->guest_cid); |
|
mutex_unlock(&vhost_vsock_mutex); |
|
|
|
return 0; |
|
} |
|
|
|
static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features) |
|
{ |
|
struct vhost_virtqueue *vq; |
|
int i; |
|
|
|
if (features & ~VHOST_VSOCK_FEATURES) |
|
return -EOPNOTSUPP; |
|
|
|
mutex_lock(&vsock->dev.mutex); |
|
if ((features & (1 << VHOST_F_LOG_ALL)) && |
|
!vhost_log_access_ok(&vsock->dev)) { |
|
goto err; |
|
} |
|
|
|
if ((features & (1ULL << VIRTIO_F_ACCESS_PLATFORM))) { |
|
if (vhost_init_device_iotlb(&vsock->dev, true)) |
|
goto err; |
|
} |
|
|
|
if (features & (1ULL << VIRTIO_VSOCK_F_SEQPACKET)) |
|
vsock->seqpacket_allow = true; |
|
|
|
for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { |
|
vq = &vsock->vqs[i]; |
|
mutex_lock(&vq->mutex); |
|
vq->acked_features = features; |
|
mutex_unlock(&vq->mutex); |
|
} |
|
mutex_unlock(&vsock->dev.mutex); |
|
return 0; |
|
|
|
err: |
|
mutex_unlock(&vsock->dev.mutex); |
|
return -EFAULT; |
|
} |
|
|
|
static long vhost_vsock_dev_ioctl(struct file *f, unsigned int ioctl, |
|
unsigned long arg) |
|
{ |
|
struct vhost_vsock *vsock = f->private_data; |
|
void __user *argp = (void __user *)arg; |
|
u64 guest_cid; |
|
u64 features; |
|
int start; |
|
int r; |
|
|
|
switch (ioctl) { |
|
case VHOST_VSOCK_SET_GUEST_CID: |
|
if (copy_from_user(&guest_cid, argp, sizeof(guest_cid))) |
|
return -EFAULT; |
|
return vhost_vsock_set_cid(vsock, guest_cid); |
|
case VHOST_VSOCK_SET_RUNNING: |
|
if (copy_from_user(&start, argp, sizeof(start))) |
|
return -EFAULT; |
|
if (start) |
|
return vhost_vsock_start(vsock); |
|
else |
|
return vhost_vsock_stop(vsock); |
|
case VHOST_GET_FEATURES: |
|
features = VHOST_VSOCK_FEATURES; |
|
if (copy_to_user(argp, &features, sizeof(features))) |
|
return -EFAULT; |
|
return 0; |
|
case VHOST_SET_FEATURES: |
|
if (copy_from_user(&features, argp, sizeof(features))) |
|
return -EFAULT; |
|
return vhost_vsock_set_features(vsock, features); |
|
case VHOST_GET_BACKEND_FEATURES: |
|
features = VHOST_VSOCK_BACKEND_FEATURES; |
|
if (copy_to_user(argp, &features, sizeof(features))) |
|
return -EFAULT; |
|
return 0; |
|
case VHOST_SET_BACKEND_FEATURES: |
|
if (copy_from_user(&features, argp, sizeof(features))) |
|
return -EFAULT; |
|
if (features & ~VHOST_VSOCK_BACKEND_FEATURES) |
|
return -EOPNOTSUPP; |
|
vhost_set_backend_features(&vsock->dev, features); |
|
return 0; |
|
default: |
|
mutex_lock(&vsock->dev.mutex); |
|
r = vhost_dev_ioctl(&vsock->dev, ioctl, argp); |
|
if (r == -ENOIOCTLCMD) |
|
r = vhost_vring_ioctl(&vsock->dev, ioctl, argp); |
|
else |
|
vhost_vsock_flush(vsock); |
|
mutex_unlock(&vsock->dev.mutex); |
|
return r; |
|
} |
|
} |
|
|
|
static ssize_t vhost_vsock_chr_read_iter(struct kiocb *iocb, struct iov_iter *to) |
|
{ |
|
struct file *file = iocb->ki_filp; |
|
struct vhost_vsock *vsock = file->private_data; |
|
struct vhost_dev *dev = &vsock->dev; |
|
int noblock = file->f_flags & O_NONBLOCK; |
|
|
|
return vhost_chr_read_iter(dev, to, noblock); |
|
} |
|
|
|
static ssize_t vhost_vsock_chr_write_iter(struct kiocb *iocb, |
|
struct iov_iter *from) |
|
{ |
|
struct file *file = iocb->ki_filp; |
|
struct vhost_vsock *vsock = file->private_data; |
|
struct vhost_dev *dev = &vsock->dev; |
|
|
|
return vhost_chr_write_iter(dev, from); |
|
} |
|
|
|
static __poll_t vhost_vsock_chr_poll(struct file *file, poll_table *wait) |
|
{ |
|
struct vhost_vsock *vsock = file->private_data; |
|
struct vhost_dev *dev = &vsock->dev; |
|
|
|
return vhost_chr_poll(file, dev, wait); |
|
} |
|
|
|
static const struct file_operations vhost_vsock_fops = { |
|
.owner = THIS_MODULE, |
|
.open = vhost_vsock_dev_open, |
|
.release = vhost_vsock_dev_release, |
|
.llseek = noop_llseek, |
|
.unlocked_ioctl = vhost_vsock_dev_ioctl, |
|
.compat_ioctl = compat_ptr_ioctl, |
|
.read_iter = vhost_vsock_chr_read_iter, |
|
.write_iter = vhost_vsock_chr_write_iter, |
|
.poll = vhost_vsock_chr_poll, |
|
}; |
|
|
|
static struct miscdevice vhost_vsock_misc = { |
|
.minor = VHOST_VSOCK_MINOR, |
|
.name = "vhost-vsock", |
|
.fops = &vhost_vsock_fops, |
|
}; |
|
|
|
static int __init vhost_vsock_init(void) |
|
{ |
|
int ret; |
|
|
|
ret = vsock_core_register(&vhost_transport.transport, |
|
VSOCK_TRANSPORT_F_H2G); |
|
if (ret < 0) |
|
return ret; |
|
return misc_register(&vhost_vsock_misc); |
|
}; |
|
|
|
static void __exit vhost_vsock_exit(void) |
|
{ |
|
misc_deregister(&vhost_vsock_misc); |
|
vsock_core_unregister(&vhost_transport.transport); |
|
}; |
|
|
|
module_init(vhost_vsock_init); |
|
module_exit(vhost_vsock_exit); |
|
MODULE_LICENSE("GPL v2"); |
|
MODULE_AUTHOR("Asias He"); |
|
MODULE_DESCRIPTION("vhost transport for vsock "); |
|
MODULE_ALIAS_MISCDEV(VHOST_VSOCK_MINOR); |
|
MODULE_ALIAS("devname:vhost-vsock");
|
|
|